Some of Lab Manager 4 Virtual Machines appear as Unavailable

After a shutdown to the system, some of our workspaces appear as unavailable. I have checked in which ESX servers are the workspaces.

Afterwards, I went to Manage > Resources > Hosts and saw that these ESX servers appear to be unavailable, as shown below.

Solution

In order to solve this problem I restarted the management agent of the ESX server by entering the following commands: service mgmt-vmware stop and service mgmt-vmware start, afterwards I restarted the Lab Manager Service “VMware vCenter Lab Manager Monitor” and it fix it.